The present invention relates generally to an agricultural crop harvester header, and more particularly to a unique side shield and latch mechanism for the outside ends of such headers.
In modern agriculture, especially in regard to harvesting forage crops, it is the current practice to cut a relatively wide swath of the crop within a range of anywhere between 10 and 16 or more feet in width, and then consolidate the crop into a narrower, substantially continuous windrow, in which form the crop is left to dry in the field until the moisture content has been reduced to a value suitable for subsequent harvesting operations, such as baling.
The most recent designs of windrower headers employ a consolidating auger operationally behind a cutterhead and rotating reel to receive the cut crop material and convey it centrally of the header from either lateral end portion thereof for feeding into a crop-conditioning mechanism, conditioning rolls, for instance. A header of this general type is shown and described in U.S. Pat. No. 3,324,639 issued to L. M. Halls et al. on Jun. 13, 1967 and U.S. Pat. No. 4,296,592 issued to Irwin D. Mcllwain on Oct. 27, 1981.
Typically, the major components of all harvester crop headers, including side shields, have been formed from sheet metal. One aspect of the instant invention is that the shield be formed by a rotational molding process.
Rotational molding is a known process used for manufacturing plastic components by first creating a mold formed in the shape of the component to be formed, and then pouring a suitable quantity of powdered polyethylene resin into the mold, after which the mold is closed, heated to about 600xc2x0 F. and slowly rotated for approximately ten minutes to evenly distribute the resin to the periphery of the mold. The heating process converts the powdered resin into an integral plastic sheeting having a generally uniform thickness conforming to the shape of the mold. The material thickness of the component part being formed is dependent on the amount of resin material first poured into the mold. By precise formation of the mold and careful calculation of the amount of resin to be applied, a generally hollow polymer component can be formed from this process.
The rotational molding process has not been traditionally used in constructing parts for agricultural equipment. Such component parts have typically been cast of metal or formed from sheet metal to provide the desired durability and function. Nevertheless, rotationally molded components are manufactured with significantly less cost than corresponding metallic parts and contain significantly less weight. Furthermore, the function of metallic components have heretofore not been duplicated, such as providing hinged closures and liquid-tight connections.
Traditional header side shields of the type under consideration herein are attached to the header or side sheet by generally vertical hinges. To open the shield for access to the shielded components, the shield is pivoted outwardly and rearwardly from the front.
Additionally, headers of this type are subject to considerable physical abuse. Not infrequently, the ends of the headers strike fence and gateposts, rocks, tree stumps, bales of hay, and the like. Often, encounters of this kind result in dents and breakage of the shield.
Plastics have been found to present particular problems in agricultural applications that relates to high ambient temperatures. One of the biggest single markets for windrower headers is in the Imperial Valley where ambient temperatures are known to rise as high as 160xc2x0 F. Plastics, particularly large pieces of plastic tend to expand more than other materials, such as steel, raising fit and alignment problems.
Accordingly, it would be highly desirable to provide a unique structure for a rotationally molded side shield and latch mechanism for a harvester header side shield that overcome the above-identified problems.
Accordingly, it is an object of the present invention to provide a header side shield that is stable, convenient and safe to operate.
It is a further object of the present invention to provide a header side shield that pivots upwardly and rearwardly to provide complete access to the operational components of the header for lubrication, inspection, adjustment, and repair.
It is a still further objected of the present invention to provide a header side shield that pivots upwardly and rearwardly about a horizontal hinge located away from most damaging obstacles and allows for access in tight quarters, such as a narrow shed or service bay, where a side opening shield could not be fully opened.
Another object of the present invention is to provide a header side shield that minimizes the interference to the flow of uncut crop material rearwardly along the side of the header.
Another object of the present invention is to provide a header styled, streamlined and modern looking in appearance that is crop-friendly to minimize crop knock down and has no sharp edges or protrusions to run down or hairpin crop materials.
It is another object of the instant invention to provide a header side shield that reduces the build-up of cut crop material and chaff between the shield and the component supporting structure (side sheet) of the header.
It is yet another object of this invention to provide an improved header side shield that is durable in construction, inexpensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective to set up, adjust and use.
It is yet another object of the present invention to provide an improved side shield that maximizes operator""s sight line, provides no sharp edges or protrusions to run down or hairpin crop materials, and uses molded-in inserts to attach latches, light brackets and hinges.
It is a still further object of the present invention to provide a side shield for a harvester header that is formed from a rotational molding process.
It is a still further object of the present invention to provide a double-walled dent-resistant side shield for a harvester header that is rotomolded of UV stabilized polyethylene material.
These and other objects are attained by providing an improved rotomolded plastic harvester header side shield. The shield is pivotable to an open position upwardly and rearwardly about a horizontal hinge located on the upper rear portion of the header. The shield is generally molded on the inside to the operational components of the header to minimize the thickness and weight of the shield and double-walled, with a totally enclosed wall cavity, to maximize its strength and durability. The shield is also open at the bottom to permit any cut crop material and chaff that may enter the shielded area to continually fall through to the ground.